%0 Journal Article %A R. I. Bogdanov %T Invariants of elementary singular points in a~plane %J Trudy Matematicheskogo Instituta imeni V.A. Steklova %D 1985 %P 227-228 %V 40 %N 3 %I mathdoc %U http://geodesic.mathdoc.fr/item/RM_1985_40_3_a9/ %G en %F RM_1985_40_3_a9